Aly Michalka Wants a 'Really Relaxed, Sentimental Wedding'

It's no surprise that director Stephen Ringer's proposal to actress Aly Michalka was straight out of a movie.

After planning a trip with her mom and sister to show them the couple's favorite spots in Big Sur, California, the Two and a Half Men actress says her now fiancé used the opportunity to set the scene to pop the big question.

"He planned that we were going to go on a hike in the morning, which didn't seem weird at all to me because we do that every time we go to Big Sur," Michalka, 25, told PEOPLE at Matt Leinart's 8th annual Celebrity Bowl Charity Event on Thursday in Hollywood.

And not even Ringer's special request for his girlfriend to get dressed up raised any red flags.

"He was like, 'Please wear a cute outfit because I want to take photos of you.' I was like, 'Okay, well, I always wear a cute outfit, but sure, I'll wear an extra cute outfit even though we're in the woods,' " she says.

After an early-morning wake up call – which included an unusual sendoff from her mom and sister A.J. – a clueless Michalka headed off on her hike with Ringer. "I didn't see it coming at all," she says of the proposal, which came once the couple arrived at the beach.

"He was like, 'Can we pray while we're out here?' ... which we've done a million times so obviously that's not strange at all," she says.

"We sat down and we prayed about our future, which was really sweet, and then he was like, 'Okay, I have a surprise for you.' I closed my eyes and he was like, 'Okay, open,' and he was down on his knees. It was really sweet. It was really precious."

Although the couple have not set a date, the bride-to-be is already dreaming of their future nuptials – and an unforgettable honeymoon.

"I definitely want a really relaxed, sentimental wedding," she says. "It doesn't have to be crazy, over the top. I don't want it to be insanely expensive – I'd rather spend it on my honeymoon. We want it to be a really beautiful, outdoor wedding ... rustic with our closest friends and family."